An unexpected encounter heralds the last case of the TV investigator Nina Petersen, in the end she makes a deadly decision. The exit of leading actress Katharina Wackernagel from the crime series "Stralsund" is spectacular. For 13 years she shaped the format, which is characterized by excitingly told stories and which is hardly imaginable without the committed, sensitive Commissioner Petersen. The episode with the subtitle "The Red Line" can be seen on Saturday at 8:15 p.m. on ZDF.

Wackernagel's farewell to "Stralsund", which is well worth seeing, was once again written and staged by director and screenwriter Martin Eigler. Right at the beginning, he confronts the main character with her past: one evening, Nina Petersen finds a seriously injured person on her doorstep. It is Benjamin Lietz (Wotan Wilke Möhring), an ex-colleague with whom she has a lot more in common than work. The two were in a relationship, Nina was expecting a child from Benjamin. During an operation, Nina was injured and the unborn baby died. Benjamin, who oscillated between good and evil as a police officer - with a penchant for crossing the red line - disappears from Nina's life.

Between anger and loyalty

Now he's back. Nina is torn between anger and loyalty. Although Benjamin is obviously in trouble again, she takes him into her home temporarily.

Then Nina is called to a crime scene in a marina by her colleague Karl Hidde (Alexander Held). Investigator Thomas Jung (Johannes Zirner) soon finds a connection between the dead man and - of all people - Benjamin Lietz. The two once shared a prison cell. It's about illegal trade in car parts and violence between rival gangs.

When Karl is kidnapped and taken onto a ferry, Nina and her colleagues Karim Uthman (Karim Günes) and Stein (Andreas Schröders) disguise themselves and drive a transporter onto the ship. They want to free Karl. Nina increasingly wonders if Benjamin has crossed the red line again. Is he involved in the kidnapping? On the ferry, the investigator manages to meet Benjamin unnoticed. He then says a sentence that breaks Nina's last spark of loyalty with her ex-boyfriend. A little later she makes a lonely and irreversible decision.